Classic roadster proportions give the Z4 a long hood and short decklid, shoulders over the wheel arches and tapers in three axes. While the Z4 is close to the ground, it is not prone to scraping at every speed bump or mild driveway entrance because the front overhang is shorter than that of many other sports cars. Short overhangs are better for handling.
The BMW Z4 is longer than the Audi TT and Mercedes-Benz SLK, and it's shorter than the Porsche Boxster, though the difference among them is only a few inches. In height and width, they are much closer. We think the BMW looks better with the top down, but it's still relatively sleek top-up, and its closed profile is similar to that of the Mercedes SLR. Gills behind the front wheels carry the substantial badges, and the side signal repeaters are located behind opaque panels in the gills; the BMW roundel is still here, but no longer serves to disguise the turn signal repeaters.
From dead-on at either end with the top down, the Z4 has strong resemblance to a scaled-down version of the 6 Series and the short-lived, Fisker-designed Z8. Sections of the taillights look like horizontal light tubes and appear to ramp up like theater lights when the lights are switched on. Adaptive brake lights deliver more red light when you hit the brake pedal hard than when merely slowing mildly. The center brake light is midway between the rear window and the tail on the trunk lid where it will not interfere with rear vision but will be covered up by an inch of snow. A single side twin-exhaust outlet signals a 28i, while the 35i and 35is have a single outlet on each side.
The Z4 cabin is immediately familiar to any BMW owner, with many of the Munich builder's hallmarks: Simple white-on-black analog instrumentation, sweeping driver-centric lines, functional controls, and a high level of fit and finish (apart from the molding seams on the map pockets). The controls and optional navigation screen are easy to read, even in direct sunlight.
There is plenty of space for two people in the Z4, the head and legroom being about what you find in a midsize SUV. Though instead of sitting upright, driver and passenger site low with legs stretched out in front. Standard manual seats and tilt/telescoping steering column provide enough adjustment to suit many driver sizes; slender types will appreciate the side bolsters on the seats and larger bodies will be framed as much by the door and console. While they may not look like thick armchairs, the seats offer excellent support over multi-hour drives; the sport seats are a bit more confining for those of wider girths yet superb for a spirited drive. The driver's footwell is large enough for size 13 shoes to comfortably operate three well-positioned pedals and there's a good dead pedal on which to rest or brace your left foot.
Cubby storage has long been the bane of roadsters, but the Z4 fixes this with door pockets that tilt out for access (they also make excellent coin catchers for the change flying out your pants pocket at the first hard bend). A bin ahead of the shifter is good for a mobile phone or pair of sunglasses. Cars without the navigation system get a cubby atop the dash. The armrest lid conceals two cupholders, which can get in the way when shifting on cars equipped with the manual transmission. A third cupholder clips in to the side of the center console on the passenger side, but we find it awkwardly placed and annoying to attach and take off.
The multifunction steering wheel is communicative and feels substantial in-hand. The M Sport wheel is even thicker and easy to maneuver. Ahead of the wheel are a large speedometer and tachometer, with smaller fuel and oil temperature gauges (more useful than coolant temperature) in the bottom. Digital displays in the center list outside temperature, mileage, trip data, and, on automatics, gear indication.
Outward visibility is good, even with the top up. Taller drivers, however, might have to look around the inside mirror on up-and-down winding mountain roads. The three-quarter view right behind the seats is mostly unobstructed because the folding top design includes two small windows.
Climate control responds immediately to an adjustment in temperature. Other controls are easy to reach and well thought out. For example, there is no need to hold the trip odo button to reset it, and some controls are designed as multifunctional with one result from a quick tap and another by depressing and holding. The parking brake is electrically operated by a switch behind the manual shifter, and it does get hot in sunshine, even when on the road.
The top opens and closes in 20 seconds without any fear it will bump you on the head. Once up, the Z4 feels just like a coupe in terms of noise abatement. Raising all four windows (use the master switch on the driver's door) allows conversation at 75 mph with the top down, and most window-down wind noise comes from the area around the seatbelts. There is no wind-blocker panel for between the headrests, as specified in early option sheets, though we have seen photos and it may become available through your dealer.
Cargo room is about average for the class at 8 cubic feet with the top up. The pass-through slot is helpful with storing longer items.